Press Releases

Californians Urged to Remove Standing Water to Reduce Mosquitoes

May 15, 2017

SACRAMENTO - The California Department of Public Health (CDPH) urges all Californians to eliminate standing water around their homes and businesses to help reduce mosquito populations in an effort to prevent Zika and West Nile virus infections.

"As the rainy season comes to an end and temperatures rise, we will see increased mosquito activity," said CDPH Director and State Public Health Officer Dr. Smith. "Residents should dump out containers that hold standing water in and around their homes and businesses. Removing water will help reduce overall mosquito numbers and protect family members and neighbors from mosquito bites and mosquito-borne diseases."

Mosquitoes breed in very small amounts of water. To help keep their numbers down, Californians should frequently check for, and eliminate, water-filled containers, clean and scrub bird baths and pet watering dishes, and dump water from dishes under potted plants. Residents are also urged to report unusual numbers of mosquitoes or day-biting mosquitoes to the local vector control agency.

With mosquito activity increasing, Californians should also protect themselves from mosquito bites at home and while traveling to areas where the Zika virus is present. To prevent bites, consistently use mosquito repellent when outside, wear long sleeves and pants, use air conditioning, and make sure window screens will keep mosquitoes out of the home.

"It is particularly important for pregnant women and couples planning to become pregnant to prevent mosquito bites because Zika virus can cause miscarriage, stillbirth, and severe birth defects if a pregnant woman becomes infected," said Dr. Smith.

Zika virus is spread primarily through mosquito bites and can also be transmitted by both men and women during sex. Most people who are infected with Zika virus do not experience any symptoms but should take precautions to avoid sexual transmission, even if they never had symptoms. Zika symptoms include fever, rash, joint pain and red eyes.

All individuals, particularly women of childbearing age, should take steps to protect themselves against mosquito bites while traveling and when they return home. Sexually active people who travel to areas with Zika virus transmission should use condoms or other barriers to avoid getting or passing Zika virus during sex. There has been no local transmission of Zika in California to date, but the mosquitoes that can carry Zika virus live in many areas of California.

West Nile virus (WNV) is also transmitted to humans and animals by the bite of an infected mosquito. WNV can cause a deadly infection in humans, and the elderly are particularly susceptible. WNV symptoms may include fever, headache, body aches, nausea, vomiting, and sometimes swollen lymph glands or a skin rash on the chest, stomach, and back. More severe symptoms, and even death, can occur. The state's first human infection of WNV this year was reported last month.

Visit the CDPH website for more information about mosquitoes, Zika and West Nile. Additional mosquito prevention information is available at www.cdc.gov.

The California Mosquito-borne Virus Surveillance and Response Program works to protect Californians from mosquito-borne viruses through environmental monitoring, laboratory testing, mosquito control, and public outreach.